A conventional coating plant typically has one or more electroplating cells, in which there is an electrolyte which contains the metals for the coating of the metal strip. The metal strip is led through the electrolyte liquid. In addition, anodes are arranged in the electrolyte. The metal strip is coated by means of an electric current between the anodes and the metal strip, which acts as a cathode. In the process, the current is controlled in such a way that a layer of a desired thickness is deposited on the metal strip.
However, in the industrial coating of metal strips there are two conflicting requirements. On the one hand, a predefined coating (weight) setpoint should, as far as possible, not be exceeded, since too thick a coating consumes an unnecessarily large amount of material and leads to higher costs. However, in order to be able to guarantee the desired properties of the metal strip, it must be ensured that the coating (weight) does not fall below a specific lower limit at any point on the strip.